Expand data.frame by creating duplicates based on group condition (3)

Question

Starting from this SO question.

Example data.frame:

df = read.table(text = \'ID  Day Count   Count_group
            18  1933    6   15
             


        

Answer 1

A generalised version of my previous answer...

#first add grouping variables
days <- 5 #grouping no of days
df$smalldaygroup <- c(0,cumsum(sapply(2:nrow(df),function(i) df$Day[i]!=df$Day[i-1]))) #individual days
df$bigdaygroup <- c(0,cumsum(sapply(2:nrow(df),function(i) df$Day[i]